The present invention relates to motion sensors for circuit activation of flashlights and the like in emergencies such as earthquakes, and devices such as flashlights having motion sensing capability.
The prior art includes numerous devices for activation of an illuminator or other alarm in response to abnormal motion. For example, U.S. Pat. No. 3,248,723 to Miethe discloses a motion sensing device in a standard flashlight casing having an audible alarm in place of the flashlight bulb. U.S. Pat. No. 4,139,845 to Washburn discloses a flashlight that is activated upon the occurrence a gross motion such as tipping the flashlight over. U.S Pat. No. 4,841,288 to Addicks discloses a lamp assembly for removably fastening to a wall, the lamp being activated by vibration of the wall.
These and other prior art devices are subject to one or more of the following disadvantages:
1. They do not remain activated after the abnormal motion has ceased;
2. They are expensive to provide because they are not compatible with standard flashlight construction;
3. They are ineffective in that they respond to gross movement only while not responding to earthquake motion that is likely to result in interruption of utility power.
Thus there is a need for a seismic circuit activator that overcomes the above disadvantages.